There are many false assumptions, both in the general population and among physicians, regarding the influence of radiation on pregnant patients and the fetus during diagnostic procedures, in spite ...of scientific facts based on studies. These false assumptions are mostly based on the idea that every diagnostic procedure using ionizing radiation is a cause for serious concern and that artificial abortion as a possible solution might be considered. We analyzed data from counseling of pregnant patients exposed to ionizing radiation during diagnostic procedures in the Merkur University Hospital during a 4-year period. In this period, 26 patients presented for counseling after exposure to diagnostic ionizing radiation during pregnancy. Results showed most of these patients to have been exposed to radiation between the 2nd and 3rd week of gestation (36%), between the 4th and 5th week 32%, before the 2nd week 24%, and after the 6th week of gestation less than 8%. To provide reasonable estimate of fetal doses, Report No. 174 from the National Council on Radiation Protection and Measurements (NCRP) was used. Data from the Report include estimate of the fetal dose from direct and indirect exposures. Th e mean doses were up to 0.01 cGy in 46.2%, 0.01-0.15 cGy in 19.2%, 0.2-1 cGy in 26.9% and 1 cGy or more in 7.7% of patients. None of the counseled patients had medical indication for abortion, even though in a small percentage of patients abortion was a personal subjective decision. Considering that there are no Croatian guidelines for counseling patients exposed to ionizing radiation during pregnancy, it is recommended to use the International Commission on Radiological Protection guidelines in the management of pregnant patients exposed to ionizing radiation.
: Gangliosides, the sialic acid—containing glycosphyngolipids, are amphiphilic compounds which in micellar form affect the properties and functions of a cellular membrane. The aim of this study was ...to test whether exogenous gangliosides supplied to cryopreservation media before freezing could protect sperm cells from cryopreservation‐induced DNA damage assessed by Comet assay. Additionally, to investigate whether gangliosides were also able to reduce membrane integrity damage, malonaldialdehyde as a measure of lipid peroxidation and sperm‐specific lactate dehydrogenase‐C4 activity as an enzyme marker of sperm membrane leakage were determined. The monosialogangliosides (GM1) and trisialogangliosides (GT1b) were examined at a concentration of 100 μM, which was above their respective critical micellar concentrations. Exogenous gangliosides were not found to protect sperm membrane from lipid peroxidation. However, a freezing‐/thawing‐induced increase in Comet parameters was equally significantly prevented by the presence of both GM1 and GT1b (P < .05), indicating that the ceramide moiety, rather than the polar groups, is involved in the protective ability of gangliosides. The observed phenomena suggest that ganglioside micelles could modulate hydrophobic properties of the sperm membrane responsible for better tolerance to DNA fragmentation, thus protecting DNA integrity from cryopreservation‐induced damage.
The aim of the present study was to evaluate genome damage induced in peripheral blood lymphocytes of Croatian health care workers occupationally exposed to cytotoxic drugs. A comprehensive ...multi-biomarker approach using the alkaline comet assay and cytogenetic endpoints (analysis of structural chromosome aberrations, SCE assay, lymphocyte proliferation kinetics and cytokinesis-block micronucleus assay) was employed. The study included two populations of subjects: 50 health care workers occupationally exposed to cytotoxic drugs and 50 control subjects matched in age, gender and smoking habit. An investigation regarding the handling practice with cytotoxic drugs was conducted in parallel. Results obtained indicate high exposure levels at workplace that should be reduced. The values recorded among the occupationally exposed subjects were as follows: mean comet tail length: 17.46±0.08
μm; the incidence of long-tailed nuclei: 54.68±3.93%; 4.48±0.33 structural chromosome aberrations per 200 cells; 5.81±0.04 SCE per 50 cells; 29.28±2.21% of high-frequency cells; proliferation rate index: 1.97±0.12; and 16.32±0.85 micronuclei per 1000 binuclear cells. All these values indicated higher levels of DNA and cytogenetic damage compared to the general population. Obtained results also confirmed that the frequency of long-tailed nuclei in the alkaline comet assay represents a helpful complement to other well-established comet parameters. The age of subjects and smoking habit significantly influenced the values of both comet and cytogenetic endpoints. Overall results of this study confirmed that handling cytotoxic drugs without appropriate safety precautions involves a potential genotoxic risk for exposed subjects. Before a strict monitoring of exposure levels on each workplace becomes a standard practice in Croatian hospitals, cytogenetic surveillance of exposed workers is also recommended, at least in cases of accidental exposure.
We have reported previously that various gangliosides, the sialic acid containing glycosphingolipids, provide protection against sperm injury caused by reactive oxygen species (ROS). In this study, ...we investigated the effect of treatment of human spermatozoa with ganglioside GT1b on hydrogen peroxide (H₂O₂)-induced DNA fragmentation and plasma membrane damage. Single-cell gel electrophoresis (Comet assay) used in the assessment of sperm DNA integrity showed that in vitro supplemented GT1b (100 μ m) significantly reduced DNA damage induced by H₂O₂ (200 μ m) (p < 0.05). Measurements of Annexin V binding in combination with the propidium iodide vital dye labelling demonstrated that the spermatozoa pre-treated with GT1b exhibited a significant increase (p < 0.05) in the percentage of live cells with intact membrane and decreased phosphatidylserine translocation after exposure to H₂O₂. Flow cytometry using the intracellular ROS-sensitive fluorescence dichlorodihydrofluorescein diacetate dye employed to investigate the transport of the extracellularly supplied H₂O₂ into the cell interior revealed that ganglioside GT1b completely inhibited the passage of H₂O₂ through the sperm membrane. These results suggest that ganglioside GT1b may protect human spermatozoa from H₂O₂-induced damage by rendering sperm membrane more hydrophobic, thus inhibiting the diffusion of H₂O₂ across the membrane.
Multielemental analysis of whole blood can provide significant information for the evaluation of nutritional status and diagnosis of certain diseases as well as for the assessment of exposure to ...potentially toxic metals. However, the quantification of multiple elements in whole blood is not easy partly because of the wide variation in element concentrations (from ng L
−1
to g L
−1
) and the complex matrix. The aim of this work was to develop a fast, sustainable, and reliable analytical method, in combination with low-power TXRF, for multielemental analysis of blood samples. Firstly, a set of experiments were carried out to select the best diluent type and dilution factor using the control material SeronormTM Trace Elements Whole Blood L-1. A critical evaluation of the parameters affecting the sample deposition on the reflector was also carried out including a study of the shape and element distribution of the deposited residue on the reflector by micro X-ray fluorescence spectrometry. Using the best analytical conditions, limits of detection estimated were in the low milligrams per kilogram range and similar to those obtained using more complex sample treatments such as digestion. Accuracy and precision of the results were in most cases acceptable (recoveries 89–102%, RSD 6–8%,
n
= 5). Only underestimated values were obtained for light elements such as potassium. To prove the applicability of the method, several blood samples from control and thyroid disease patients were analyzed. Despite the fact that more samples need to be analyzed, it seems that Zn and Br contents in some of the patients are significantly higher compared to control samples.
Graphical abstract
Several studies have reported radioprotective, antimutagenic, anti-inflammatory, antinociceptive, and anticancer effects of bee venom both in the cell and the whole organism. The aim of this study ...was to assess the effects of a single high dose of 100 μg mL-1 of whole bee venom in human lymphocytes in vitro over a variety of time spans (from 10 min to 24 h). After the treatment, we used the comet assay and micronucleus test to see the effect of bee venom on the cell. The comet assay confirmed that the venom damaged the DNA molecule. Tail length, tail intensity, tail moment showed a significant increase (P<0.05). The percentage of long-tailed nuclei (LTN) with the tail length exceeding the 95th percentile also increased in a time-dependent manner. The micronucleus parameters (number of micronuclei, nucleoplasmic bridges, and nuclear buds) also showed a significant time-dependent increase (P<0.05). This research indicates that high concentrations of bee venom can lead to cellular instability. Further research is needed to understand the mechanism of action of bee venom and its components in human cells and to see if this natural product may find application in medicine.
Cilj ovog istraživanja je procjena staničnog statusa ljudskih limfocita periferne krvi nakon tretmana visokom koncentracijom pčelinjeg otrova u in vitro uvjetima primjenom alkalnog kometnog testa i mikronukleusnog testa. Limfociti su bili izloženi pčelinjem otrovu u koncentraciji od 100 μg mL-1 u različitom vremenu (od 10 min do 24 h). Rezultati kometnog testa upućuju na oštećenje molekule DNA povećanjem parametara kometnog testa (dužina repa, intenzitet repa i repni moment) te prisutnost limfocita s visokom učestalosti kometa s dugim repovima (LTN). U tim stanicama učestalost LTN premašuje 95% ukupne raspodjele vrijednosti LTN dobivene za sve stanice kontrolnog uzorka. Parametri mikronukleusnog testa (broj mikronukleusa, nukleoplazmatski mostovi i nuklearni pupovi) također pokazuju značajan porast u odnosu na odgovarajući kontrolni uzorak (P<0,05). Rezultati dobiveni ovim tehnikama upućuju na to da pčelinji otrov u visokoj koncentraciji uzrokuje staničnu nestabilnost te na potrebu daljnjih istraživanja mehanizama djelovanja pčelinjeg otrova i njegovih sastavnica na ljudske stanice u svrhu primjene prirodnih spojeva posebice u medicinskoj praksi.
Spontaneous and chemotherapy-induced sister chromatid exchanges (SCES) and lymphocyte proliferation rate index (PRI) in cultured peripheral lymphocytes were evaluated in 30 patients with diagnosed ...breast cancer before and after adjuvant chemotherapy and in 30 healthy women with no known familial history of breast cancer. Before chemotherapy, the breast cancer patients had a significantly increased background level of SCE, and lowered PRI as compared with the healthy women. Marked inter-individual variations were observed in both endpoints among the patients. Significantly elevated frequency of SCE and depressed PRI were recorded in blood samples collected after the first cycle of chemotherapy, with high inter-individual variations in the responses to the chemotherapy. FAC (5-fluorouracil, adriamycin and cyclophosphamide) protocol was the most genotoxic of the protocols studied, but also AC (adriamycin, cyclophosphamide) and CMF (cyclophosphamide, methotrexate and 5-fluorouracil) clearly increased SCE. All protocols significantly retarded lymphocyte proliferation in vitro. Our findings indicate that both SCE and PRI may serve as sensitive biomarkers for the routine detection of critical lesions produced by the administration of antineoplastic drugs in the clinical setting, as well as for possible screening of high-risk individuals among patients who have successfully completed chemotherapy.
Human & Experimental Toxicology (2007) 26
, 391—399
T-2 Toxin: Incidence and Toxicity in Poultry Sokolovic, Marijana; Garaj-Vrhovac, Verica; Simpraga, Borka
Arhiv za higijenu rada i toksikologiju,
03/2008, Letnik:
59, Številka:
1
Journal Article
Recenzirano
Odprti dostop
T-2 toxin is the most toxic type A trichothecene mycotoxin. It is the secondary metabolite of the Fusarium fungi, and is common in grain and animal feed. Toxic effects have been shown both in ...experimental animals and in livestock. It has been implicated in several outbreaks of human mycotoxicoses. Toxic effects in poultry include inhibition of protein, DNA, and RNA synthesis, cytotoxicity, immunomodulation, cell lesions in the digestive tract, organs and skin, neural disturbances and low performance in poultry production (decreased weight gain, egg production, and hatchability). Concentrations of T-2 toxin in feed are usually low, and its immunosuppressive effects and secondary infections often make diagnosis difficult. If at the onset of the disease, a change in diet leads to health and performance improvements in animals, this may point to mycotoxin poisoning. Regular control of grain and feed samples is a valuable preventive measure, and it is accurate only if representative samples are tested. This article reviews the incidence and toxic effects of T-2 toxin in poultry.
T-2 toksin je najtoksičniji predstavnik trikotecenskih mikotoksina tipa A. On je sekundarni produkt metabolizma plijesni roda Fusarium i često je prisutan u žitaricama i hrani za životinje. Štetni učinci uočeni su u eksperimentalnih životinja i životinja u uzgoju. On se povezuje s pojavom bolesti ljudi od mikotoksikoza. Učinci toksina u peradi su višestruki: inhibicija sinteze proteina, DNA i RNA, citotoksični učinak, imunomodulatorni učinak, oštećenje stanica probavnog sustava, organa i kože, živčani poremećaji te pad proizvodnih karakteristika u uzgoju peradi (slabiji prirast, pad nesivosti i valivosti). Koncentracije T-2 toksina u hrani redovito su vrlo malene, a zbog imunosupresivnog djelovanja toksina te istodobne sekundarne infekcije bolest se često teško dijagnosticira. Pri pojavi bolesti promjenom hrane može doći do poboljšanja zdravstvenog stanja, što također upućuje na moguće trovanje mikotoksinima. Redovita kontrola uzoraka žitarica i hrane za životinje jedna je od preventivnih mjera, a detekcija mikotoksina u žitaricama i hrani pouzdana je samo ako se ispituje reprezentativan uzorak. U radu su opisani učestalost i toksični učinci T-2 toksina u peradi.
► Carboplatin resistant laryngeal carcinoma 7T cells are cross resistant to curcumin. ► Reduced accumulation of curcumin is involved in curcumin resistance of 7T cells. ► Curcumin induces less ROS, ...lipid and DNA damage and apoptosis in 7T cells.
Curcumin is a natural compound that exhibits a wide range of beneficial effects, among them the anti-tumor activity. Recently it was shown that curcumin may be efficient against drug resistant tumor cells. The goal of our investigation was to examine if human laryngeal carcinoma cells resistant to carboplatin display sensitivity to curcumin, as compared to parental cells, and if this sensitivity is altered, to determine the molecular mechanisms that are responsible for it. We found that carboplatin resistant 7T cells were also cross resistant to curcumin. After the treatment with equimolar concentration of curcumin, 7T cells exhibited lower intracellular accumulation of curcumin which coincided with reduced formation of reactive oxygen species (ROS), diminished lipid and DNA damage followed by reduced induction of apoptosis and expression of heat shock protein 70 (Hsp70), as compared to parental HEp-2 cells. However, after the treatment with equitoxic concentration of curcumin, intracellular accumulation and all the explored downstream effects were similar in both cell lines suggesting that resistance of 7T cells to curcumin was based on its reduced intracellular accumulation. Since curcumin accumulates mostly in the membranes, we explored the fatty acid composition of both cell lines, but we did not find any difference between them.
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